In reply to Mike Nolan: DofE requires you to have one cooked meal a day but does not require it to be in/on a Trangia - other cookers are available and, for me at least, are lighter and easier to use.
Really good suggestions above but DofE has its' requirements (and an assessor) and it should be down to your personal dietary taste/needs. Also, as you will be in a group, check out what others like, foodwise, and pool resources. For info, stuff I've cooked/eaten/enjoyed ....
Breakfast
Instant porridge sachets decanted into poly bags with additional powdered milk and dried fruit and/or nuts of choice
Lunch
Before going, cook large pizza with many toppings, allow to cool, fold over, cut into slices of a suitable size and wrap in clingfilm - usually lasts for a couple of days
pitta breads/oatcakes with squeezy cheese (choice of flavours available) or even your choice of solid cheeses, peperami, chorizzo (this for the next couple of days)
Main meal
couscous/pasta/mash etc with cupasoups/pesto/pasta sauces etc for flavourings and added peperami/chorizzo/cheese etc for interest
Snacks
fresh fruit for first day or so, nuts/dried fruit/sweets in "trailmix", malt loaf, choccy bars etc
Extras - salt/pepper/sugar/sauce sachets from fast food places are ideal flavour enhancers as are small poly bags of curry/chilli/garlic powder, mixed herbs etc - for a full gourmet experience!
The idea is try and keep weight down so dehydrated stuff is ideal - as long as you can source water! Most of all ENJOY both the exped and the grub!
Apologies for the long ramble, but I likes me grub! Cheers, Col